通过在 C=N 部分的 C 位附近引入甲酰基或酰基,首次成功实现了喹喔啉支架中 C=N 键的反应性 umpolung。因此,C=N 键的反向反应性使得烷基格氏试剂能够在 N 端而不是 C 端直接进行亲核攻击,从而为合成 quinoxalin-2(1 H )-one提供了一种前所未有的有效方法涉及串联 N-烷基化/C─C 键断裂过程的衍生物。
Synthesis of functionalized benzimidazoles and quinoxalines catalyzed by sodium hexafluorophosphate bound Amberlite resin in aqueous medium
作者:Pranab Ghosh、Amitava Mandal
DOI:10.1016/j.tetlet.2012.09.045
日期:2012.11
for the selective synthesis of 1,2-disubstitutedbenzimidazoles and quinoxalines in water–methanol (1:1) mixture with the aid of resin bound hexafluorophosphate ion as catalyst is reported. The method is also effective for the incorporation of quinoxaline nucleus at the A ring of pentacyclic triterpenoid, friedelin. A plausible mechanism for the formation of disubstituted benzimidazole has also been suggested
Electrochemical Arylation of Electron‐Deficient Arenes through Reductive Activation
作者:Pan Wang、Zhenlin Yang、Ziwei Wang、Chenyang Xu、Lei Huang、Shengchun Wang、Heng Zhang、Aiwen Lei
DOI:10.1002/anie.201909600
日期:2019.10.28
An electrochemical method has been developed to achieve arylation of electron-deficientarenes through reductive activation. Various electron-deficientarenes and aryldiazonium tetrafluoroborates are amenable to this transformation within the conditions of an undivided cell, providing the desired products in up to 92 % yield. Instead of preparing diazonium reagents, these reactions can begin from anilines
The effective Cp*IrIII‐catalyzed [4+2] tandem cyclization reaction of β‐keto sulfoxonium ylides and o ‐phenylenediamine has been reported for the first time, furnishing monosubstituted quinoxaline and its derivatives with moderate to excellent yield. This novel protocol exhibits broad substrate scope as well as feasibility for late‐stage modification of drug molecules
首次报道了有效的Cp * Ir III催化β-酮基硫代氧鎓基化物和邻苯二胺的串联[4 + 2]环化反应,提供了中等至优异收率的单取代喹喔啉及其衍生物。该新方案展示了广泛的底物范围以及药物分子后期修饰的可行性
γ-Maghemite-silica nanocomposite: A green catalyst for diverse aromatic N-heterocycles
作者:Pranab Ghosh、Amitava Mandal、Raju Subba
DOI:10.1016/j.catcom.2013.06.026
日期:2013.11
gamma-Maghemite-silica nanocomposite has been applied as a green catalyst to synthesize variety of aromatic N-heterocycles under solvent free conditions. Characterization was done by modern analytical tools (UV, IR, AAS, DSC, EDXRF, powdered XRD, EPR, Mossbauer and TEM). Mild reaction conditions and recyclability have made the present protocol both environmentally and economically viable. (c) 2013 Elsevier B.V. All rights reserved.
Electrochemical Oxidative C–H Arylation of Quinoxalin(on)es with Arylhydrazine Hydrochlorides under Mild Conditions
作者:Shengjie Song、Xiangjun Shi、Yunsheng Zhu、Quanlei Ren、Peng Zhou、Jiadi Zhou、Jianjun Li